Electrical connectors



A ril 18, 1967 s. GODEL ELECTRICAL CONNECTORS 3 Sheets-Sheet 1 Filed Sept. 23, 1964 lav- MMSH m m m ...3 I ME f T F 3 l m m E 3 5 III m E 4 m E 0 I1 4 \E G w m w E l l bl a m mbuu lub E NH&/O 1/. m W E w. o M m M/ t n. A? w y v i m m) m w FIG. I.

ATTORNFY 3 Sheets-Sheet 2 ISI INVENTOR Siegfried Godel April 18, 1967 5 GQDEL ELECTRI CAL CONNECTORS Filed Sept. 23, 1964 FIG.2.

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ATTORNI-Y United States Patent 3,315,209 ELECTRICAL CONNECTORS Siegfried Godel, Norwalk, Conn, assignor to American Machine 8: Foundry Company, a corporation of New Jersey Filed Sept. 23, 1964, Ser. No. 398,650 Claims. (Cl. 339-118) This invention relates to electrical connection devices and more particularly to connectors of the type comprising two spaced conductive elements interconnected by a pin held in compression between the two conductive elements. The invention also includes improved connector pins for such devices.

In the electrical arts, there is frequent need for providing an electrical connection between two spaced conductive elements without attaching any connector member to either conductive element. Such requirements are met, for example, in the common plug board or cross-connecting devices employed to establish selective connections between any of various pairs of conductive elements arranged in matrix fashion. Though many prior-art connection devices of this general type have been proposed, such devices are usually characterized by disadvantages which have created an active demand for improvement. Typically, prior-art devices of this type either employ relatively complicated elements designed to assure establishment of good low-resistance connections, or achieve simplicity at the cost of high electrical resistance. In prior-art devices achieving adequately low resistance, the connector pins employed are usually unduly fragile and costly.

It is a general object of this invention to provide such a connector device which is free from such disadvantages.

Another object is to provide an electrical connector comprising two conductive elements presenting flat, opposing surfaces, and an axially compressible connector pin engaged between said surfaces and having flat end faces disposed in face-to face engagement with the respective ones of said surfaces in such fashion as to achieve a low resistance connection.

A further object is to devise an improved resiliently compressible connector pin fabricated in its entirety from a single sheet metal blank.

Yet another object is to provide such a connector pin having flat, parallel end faces which retain their parallel relationship when the pin is axially compressed between two parallel surfaces.

A still further object is to devise an electrical connector of the type described which can be manufactured at low cost and which involves no fragile parts.

Typically, the invention can be applied to electrical interconnecting devices of the type disclosed and claimed in copending application Ser. No. 398,532, filed concurrently herewith by Siegfried Godel and entitled, Electrical Interconnecting Devices. Such devices include an apertured programming board of insulating material disposed between two spaced members each carrying a separate group of conductive elements to be interconnected. The connector pins in accordance with the invention are formed 'by bending an elongated strip, of thin spring sheet metal on spaced transverse lines in such fashion that the strip is in the form of alternate axially extending portions and transversely extending portions. Two of the transversely extending portions are located each at a different end of the connector pin and constitute the end faces for engagement with the conductive elements to be interconnected by the pin. The axially extending portions can be considered as arranged in pairs, with the axially extending portions of each pair joined to opposite sides of a common transversely extending portion. Thus,

adjacent ones of the axially extending portions are located at opposite sides of the connector pin. When'the pin is in its relaxed condition, the transversely extending portions lie at right angles to the axially extending portrons. When the connector pin is engaged in compression between the two conductive elements which it is to interconnect, the bends between the axial and transverse portions become more acute, the axially extending portions moving into an overlapping relation so that the pin is effectively shortened.

In particularly advantageous embodiments, the connector pin comprises an additional resilient srtip bent in the same general fashion as the first, corresponding transverse portions of the two strips being joined at one end of the pin, and corresponding axially extending portions of the two strips being disposed on opposite sides of the pm.

In order that the manner in which the foregoing and other objects are achieved in accordance with the invention can be understood in detail, one particularly advantageous embodiment of the invention will be described with reference to the accompanying drawings, which form a part of this specification, and wherein:

FIG. 1 is a side elevational view of an electrical interconnecting device embodying the invention;

FIGS. 2 and 3 are opposite end elevational views of the device of FIG. 1;

FIG. 4 is a top plan view of the device of FIG. 1;

FIG. 5 is a top plan view of the programming board of the device of FIG. 1;

FIG. 6 is a top plan view of the base member of the device of FIG. 1;

FIG. 7 is a plan view of a sheet metal blank from which each of the connector pins for the device of FIG. 1 are formed; and

FIGS. 8 and 9 are side elevational views of a complete connector pin, FIG. 8 illustrating the relation of the pin to the supporting programming board, both FIGS. 8 and 9 illustrating the pin in relaxed condition.

Referring now to the drawings in detail, it will be seen that the invention is shown as applied to a plugboard type of interconnecting device including a base member 110, a programming board or intermediate member 111 and an upper member 112. Base member is in the form of a flat, rigid plate of insulating material, the plate being rectangular in plan and having long sides 113 and 114 and short sides 115 and 116. Standoff insulators 117 are provided, by which the base member can be aflixed to a part of the equipment with which the device is to be used. On its upper surface 118, member 110 is provided with ten mutually parallel elongated conductive strips 119 which are spaced equally from each other and extend parallel to the short sides 115, 116. Adjacent side 114, the conductive strips are provided at their ends with connection terminals 120 in the nature of pins which extend through base member 110 and project from the lower surface 121 thereof. The conductive strips 119 can be provided as printed circuit elements or established on the upper face of member 110 in any other conventional fashion.

The group of conductive elements constituted by strips 119 is offset from the center of member 110 toward edge 115. In the space between the conductive strips 119 and edge 116, there are provided shor-t conductive strips 122 which extend parallel to the long sides 113, 114 and, at their ends adjacent side 116, are connected to terminal pins 123 which project from the lower surface 121 of base 110.

Adjacent short side 115, there is secured to the upper face of base 110 a pivoted catch member 124. Member 124 includes a shank 125 and an enlarged tip providing a downwardly facing shoulder 126 and an upwardly and outwardly slanting cam face 127. The lower end of shank 125 is disposed between the legs of a generally U- shaped mounting block 128 secured to base 1, as by screws 129. The shank 125 of the catch member is pivot-ally supported by a suitable shaft (not shown) extending horizontally through the legs of mounting block 128 parallel to the short side 115, a torsion spring (not shown) being provided in the usual fashion to bias catch member 124 pivotally toward short side 116.

Base member 110 also carries a second pivoted catch member 130 which is identical with catch member 124. Catch member 130 includes a downwardly facing shoulder 131 and an upwardly and outwardly slanting cam surface 132. Catch member 130 is mounted for pivotal movement about an axis parallel to side 116 and is resiliently biased in a direction tending to pivot the member toward side 115.

The programming board or intermediate member 111 is in the form of an integral body of electrically insulating material and is generally rectangular in plan, including long sides 133 and 134, and short sides 135 and 136. The lower surface 137 of member 111 is fiat and extends throughout the entire length and width of member 111. Adjacent the lower surface thereof, the body of member 111 is cut away at the corners to accommodate the mounting screws for the standoff insulator 117. Also, downwardly opening notches of suitable size and configuration are provided to accommodate the mounting block which supports catch members 124 and 130.

Adjacent short side 135, member 111 includes a relatively thick, upwardly projecting portion 138 defined on one side by short side 135 and on the'other side by a surface 139 which extends parallel to side 135 and is provided with an inwardly opening groove 140 extending for the full width of member 111. Side 135 is provided with a notch 141 to accommodate the shank of pivoted catch member 124. In the same location, the top of portion 138 is notched to provide a horizontal surface 142 to cooperate with shoulder 126 of catch member 124.

Adjacent side 136, member 111 has a thickened, upwardly projecting portion 143, FIG. 1, presenting a higher top surf-ace portion 144 and a second top surface por* tion 145 spaced slightly therebelow, surface portion 143 lying in the same plane as the bottom wall of groove 140. Side 136.is provided with a notch 146 to accommodate the shank of pivoted catch member 130. Surface portion 144 is disposed to cooperate with the shoulder 131 of catch member 130.

Between thickened portions 138 and 143, member 111 presents a flat upper surface 147. In this area of member 111, there are provided one hundred apertures 148 arranged in ten equally spaced rows extending parallel to the short sides 135 and 136 of member 111, the spacing between the ten rows of apertures being equal to the spacing between the conductive strips 119. Apertures 148 are identical, each being of square transverse cross section and uniform throughout its length, opening both through lower surface 137 and upper surface 147.

In the area of member 111 defined by upper surface portion 145, there are provided ten apertures 1'49 spaced equally in a row parallel to the short sides 135, 136, the spacing between apertures 149 being equal to the spacing between apertures 148. Apertures 149 are each identical to apertures 148.

In the area defined by surface portion 144, member 1 11 is provided with two upwardly facing, internally threaded bores 151 which extend at right angles to surface 144.

Upper member 112 is in the form of a rigid rectangular plate of insulating mate-rial having long sides 152 and 153 and short sides 154 and 155. The flat lower surface 156 of member 112 is provided with ten elongated electrically conductive strips 157 which are equally spaced, mutually parallel, and extend parallel to the long sides 152 and 153 of member 112. Strips 157 are spaced apart by distances equal to the spacing between apertures 148. The electrically conductive strips 157 can be established by printed circuit procedures or any other suitable method.

Short side 154 of member 112 is straight and uninterrupted, the thickness of member 112 being such that the portion thereof adjacent side 154 can be accommodated snugly within groove 140. Short side is interrupted by a notch 158 of adequate size to freely accommodate the upper portion of pivoted catch member 130. Member 112 is provided with openings to accommodate the shanks of fastening screws 159, the screws being so located as to allow threaded engagement of the tips thereof with bores 151 when the side portion of member 112 at 155 is properly engaged in groove 140.

Since electrically conductive strips 157 extend parallel to the long sides 152 and 153 of member 112, and since that member is installed with its short sides parallel to the short sides of base 110, the electrically conductive strips 157 extend across strips 119 on the base at right angles, each strip 157 crossing all of the strips 119. Thus, the two groups of conductive strips are arranged to form a matrix, with strips 119 defining the X-axis and strips 157 defining the Y-axis. Apertures 148 are so arranged that each aperture is located at a different one of the points of crossing of strips 119 and 157. In this embodiment, engagement of the catch members 124, 130 respectively in notches 141 and 146 serves to maintain the intermediate member 111 in properly oriented position with respect to base 110, while the screws 159 fix the upper member 112 in proper relation to the intermediate member.

Interconnection between the conductive strips 119 and 157, and between strips 157 and the short strips 122, is accomplished by means of a plurality of connector pins 160 each disposed in a difierent one of the apertures 148, 149. Pins 160 are identical, being made from a blank of thin beryllium copper or like spring material, a typical blank 161 being illustrated in FIG. 7. The blank includes two greatly elongated rectangular portions 162 and 163 disposed in side-by-side relation, the two portions being formed from the same piece of material and joined in an area indicated at 164, which will be centrally located with respect to the bottom end of the completed connector pin.

Considering first strip 162, and comparing FIGS. 7, 8 and 9, it will be seen that the strip is bent at a plurality of transverse lines defining portions 165-172, portion 165 being the lowermost portion and portion 172 the uppermost portion. Portion 166 overlies portion 165 and is in face-to-face engagement therewith. Portions 167, 169 and 171 are vertical portions, while portions 168, 176 and 172 extend horizontally, that is, transversely of the completed pin. Strip 163 is similarly bent about transverse lines to provide portions 173-180. Portion 173 is bent to overlie base portion 174 and be in faceto-face contact with the upper surface thereof. Portions 175, 177 and 179 are vertically disposed, extending axially of the pin, while portions 176, 178 and 180 are horizontally disposed, extending transversely of the pin. For each of the strips 162 and 163, there are thus alternate portions extending transversely and axially, the axial portions for each strip being alternately on different sides of the strip, as will be clear from FIG. 8. Further, the relative positions of the two strips are reversed, so that, in any one portion of the connector pin, the vertical part of one strip will be on the opposite side of the pin from the vertical part of the other strip.

The Widths of the two strips 162, and the lengths of the transverse or horizontally extending portions 165, 166, 168, 173, 174 and 176 are such that the transverse dimensions of the corresponding part of the completed connector pin will be slightly smaller than the transverse cross section of apertures 1'48, 149 in intermediate member 111. In this connection, it will be noted that portions 165, 166, 168, 173, 174 and 176 are of equal length, this length being equal to the combined widths of the two strips 162 and 163. Accordingly, the lower portion of the completed connector pin has an essentially square transverse cross section.

Portions 170, 172, 178 and 180, all located in the upper portion of the finished connector pin, are materially longer than transverse portions in the lower part of the connector pin. Accordingly, as will be clear from FIG. 8, portion 170 projects beyond the common plane occupied by vertical portions 167 and 177, providing a shoulder at 181 for engagement with the upper surface 147 of member 111. Similarly, portion 178 projects beyond the common plane occupied by portions 169 and 175, providing a shoulder 182 for engagement with surface 147. The normal or relaxed length of each connector pin 160 is such that, when the pin is inserted in one of the apertures 148, 14-9 and shoulders 181 and 182 are seated on surface 147, the lower tip of the connector pin, defined 'by portions 165 and 174, will project well below the lower surface 137 of member 111, as seen in FIG. 8. Assuming that member 111 has been removed from the assembly, and that pins 160 have been inserted therein, all of the transverse portions, such as portions 165 and 172, can be considered as lying essentially at right angles to the axially extending portions, such as portions 166 and 171.

Since, when the pins 160 are in their normal or relaxed conditions, the space between the lower surfaces of portions 165 and 174 and the upper surfaces of portions 172 and 180 is materially greater than the space between the exposed faces of conductive strips 119 and the exposed faces of conductive strips 157, in the assembled device, it will be clear that, once the device is assembled, any of the pins 160 which have been inserted in member 111 will be held under axial compression, with the lower surfaces of portions 165' and 174 in flush engagement with conductive strips 119 and the upper surfaces of portions 172 and 180 in flush engagement with conductive strips 157. In essence, such compression of the connector pins causes the angles between the transverse portions and the longitudinal portions to become acute, rather than right angles. Thus, for example, when the pin 160 seen in FIG. 8 is axially compressed, it can be considered that portion 167 will be shifted upwardly, as viewed, and portion 169 shifted downwardly, so that transverse portion 168 slants downwardly from right to left, as viewed. In the preferred form of the device, all of the compressive axial force applied to the pin is assumed by the type of distortion just mentioned, so that it is unnecessary to have any of the axially extending portions of the pin 'be under such compressive stress as would tend to materially bow the same.

The connector pins described with reference to FIGS. 7 and 9 have the distinct advantage of presenting relatively broad, fiat contact surfaces for engagement with the cooperating conductive strips 119, 157, thus assuring good electrical contact of relatively low resistance. It will be noted that, when flat conductive strips are employed on the base and upper member, as in the present embodiment, there is no distortion of the flat end surfaces presented by the contact pin. Accordingly, the problem of unpredictable non-uniformity of contact en gagement is completely avoided in this embodiment.

While a certain advantageous embodiment has been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. In an electrical connector, the combination of first and second conductive elements each having a flat surface;

means supporting said conductive elements in spaced relation with said flat surfaces parallel and facing each other;

a connector element engaged between said flat surfaces,

said connector element comprising an elongated strip of thin resilient sheet metal bent upon a plurality of spaced transverse lines to provide a series of alternate axially extending portions and transversely extending portions, two of said transversely extending portions being located each at a different end of the connector element, adjacent ones of said axially extending portions being located at different sides of the connector element;

said connector element further comprising an additional elongated strip of thin resilient sheet metal bent upon a plurality of spaced transverse lines to provide a series of alternate axially extending portions and transversely extending portions;

two of said transversely extending portions of said additional strip being located each at a different end of the connector element;

the transversely extending portions of both of said strips at one end of the connector element being joined together;

corresponding ones of said axially extending portions of said strips being located on opposite sides of the connector element; and

each of said strips being provided with an additional transversely extending portion;

said additional transversely extending portions both being located at the same end of the connector element and overlying in face-to-face relation the corresponding ones of said first-mentioned transversely extending portions.

2. In an electrical connector, the combination of first and second conductive elements;

an insulating member having an aperture and a flat surface through which said aperture opens;

a connector element comprising an elongated strip of thin, resilient sheet metal bent upon a plurality of longitudinally spaced, transversely extending lines to provide a plurality of alternate axially extending portions and transversely extending portions, two of said transversely extending portions being located each at a different end of the connector pin, there being at least three of said axially extending portions, the adjacent ones of said axially extending portions be ing located at different sides of the connector element;

the one of said transversely extending portions located at one end of the connector element and the next adjacent one of said transversely extending portions both being materially longer than the others of said transversely extending portions; the. length of said longer transversely extending portions being greater than the maximum transverse dimension of said aperture; said connector element extending through said aperture with said longer transversely extending portions located beyond the end of said aperture which opens through said flat surface; and means supporting said first and second conductive elements and said insulating member with the latter disposed between said conductive elements;

said aperture opening toward both of said conductive elements; said flat surface of said insulating member being spaced from the one of said conductive elements which it faces;

the relaxed length of said connector element being greater than the spacing between said conductive elements, said said connector element being held in compression between said conductive elements.

3. An electrical connector in accordance with claim 2 and wherein the space between said fiat surface of said insulating 7 t 8 member and the one of said conductive elements strips at one end of the connector element being which it faces is at least as great as the space between joined together; said longer transversely extending portions of said corresponding ones of said axially extending porconnector element. tions of said strips being located on opposite sides of the connector element.

4. An electrical connector in accordance with claim 2 and wherein said aperture is of rectangular transverse cross-section. References Cited by the Examiner 5. An electrical connector in accordance with claim 2 UNITED STATES PATENTS 1nd ,Whemm 2,161,598 1/1939 Torkelson 317-412 XR said connector element comprises a second elongated 10 3 048 812 8/1962 Heidler strip of thin, resilient sheet metal bent at a plurality 3158419 11/1964 Meyer of longitudinally spaced transversely extending lines 3:223:957 12/1965 Cannon 5 XR to provide a series of alternate axially extending portions and transversely extending portions respective- FOREIGN PATENTS 1y identical to the axially extending portions and 15 295,765 3/1923 Great Britaintransversely extending portions of said first-mentioned Strip; EDWARD C. ALLEN, Primary Examiner.

the transversely extending portions of both of said PATRICK A. CLIFFORD, Examiner. 

1. IN AN ELECTRICAL CONNECTOR, THE COMBINATION OF FIRST AND SECOND CONDUCTIVE ELEMENTS EACH HAVING A FLAT SURFACE; MEANS SUPPORTING SAID CONDUCTIVE ELEMENTS IN SPACED RELATION WITH SAID FLAT SURFACES PARALLEL AND FACING EACH OTHER; A CONNECTOR ELEMENT ENGAGED BETWEEN SAID FLAT SURFACES, SAID CONNECTOR ELEMENT COMPRISING AN ELONGATED STRIP OF THIN RESILIENT SHEET METAL BENT UPON A PLURALITY OF SPACED TRANSVERSE LINES TO PROVIDE A SERIES OF ALTERNATE AXIALLY EXTENDING PORTIONS AND TRANSVERSELY EXTENDING PORTIONS, TWO OF SAID TRANSVERSELY EXTENDING PORTIONS BEING LOCATED EACH AT A DIFFERENT END OF THE CONNECTOR ELEMENT, ADJACENT ONES OF SAID AXIALLY EXTENDING PORTIONS BEING LOCATED AT DIFFERENT SIDES OF THE CONNECTOR ELEMENT; SAID CONNECTOR ELEMENT FURTHER COMPRISING AN ADDITIONAL ELONGATED STRIP OF THIN RESILIENT SHEET METAL BENT UPON A PLURALITY OF SPACED TRANSVERSE LINES TO PROVIDE A SERIES OF ALTERNATE AXIALLY EXTENDING PORTIONS AND TRANSVERSELY EXTENDING PORTIONS; TWO OF SAID TRANSVERSELY EXTENDING PORTIONS OF SAID ADDITIONAL STRIP BEING LOCATED EACH AT A DIFFERENT END OF THE CONNECTOR ELEMENT; THE TRANSVERSELY EXTENDING PORTIONS OF BOTH OF SAID STRIPS AT ONE END OF THE CONNECTOR ELEMENT BEING JOINED TOGETHER; CORRESPONDING ONES OF SAID AXIALLY EXTENDING PORTIONS OF SAID STRIPS BEING LOCATED ON OPPOSITE SIDES OF THE CONNECTOR ELEMENT; AND EACH OF SAID STRIPS BEING PROVIDED WITH AN ADDITIONAL TRANSVERSELY EXTENDING PORTION; SAID ADDITIONAL TRANSVERSELY EXTENDING PORTIONS BOTH BEING LOCATED AT THE SAME END OF THE CONNECTOR ELEMENT AND OVERLYING IN FACE-TO-FACE RELATION THE CORRESPONDING ONES OF SAID FIRST-MENTIONED TRANSVERSELY EXTENDING PORTIONS. 